The following description of the background of the invention is provided simply as an aid in understanding the invention and is not admitted to describe or constitute prior art to the invention.
Dihydrotestosterone (DHT) [(17β-hydroxy-5a-androstan-3-one)] is a steroid hormone with a molecular weight of 299.4 Daltons. DHT is a potent androgen synthesized by peripheral tissues from testosterone. Excessive DHT secretion can produce acne, hirsutism and virilization via conversion to testosterone. DHT is a causal agent in prostate hyperplasia and measurements in blood can be used to assess compliance and response to inhibitors of testosterone to DHT conversion.
Mass spectrometric methods for measuring DHT in a sample have been reported. See, e.g., Chang, Y., et al., Analyst 2003, 128:363-8; Caruso, D., et al., Neurochem Int 2008, 52:560-8; Wang, C., et al., Steroids 2008, 73:1345-52; Zhao, M., et al., Steroids 2004, 69:721-6; Janzen, N., et al., J Chroma B 2008, 861:117-22; Licea-Perez, H., et al., Steroids 2008, 73:601-10; Kashiwagi, B., et al., J Andrology 2005, 26:586-91; Kashiwagi, B., et al., Urology 2005, 66:218-23; Umera, M., et al., Cancer Sci 2007, 99:81-86; and Mohler, et al., U.S. patent application Ser. No. 11/973,127 (filed Oct. 8, 2007).